Some Dynamic Methods for Determination of Young's Modulus

Properties of high-temperature ceramics and cermets :

“…Once Young's modulus and the shear modtdus were determined, Poisson's ratio was calculated from the following equation. (11) For the 3-in. specimens, where Ej could not be determined, Ef^, or Efe (eq (5) or (6)) was used in eq (11). However, the importance of an accurate value of n for the determination of Ef^, or Efe has already been mentioned.…”

“…Thus, the possibility of the occurrence of creep, elastic hysteresis, plastic flow, or similar effects is reduced to a minimum [5].…”

“…However, the importance of an accurate value of n for the determination of Ef^, or Efe has already been mentioned. The procedure that was followed, then, was to assume a reasonable value of M in calculating Ef^^o r E^^from eq (5) or (6) The precision of the resonant frequency 1 measurements has been given as about 1 part in I 3,000 (2.3b The first condition was designed to test the uniformity of fabrication, whereas the latter condition tested the uniformity of batch preparation.…”

“…The numerical constant in eqs (5) and (6) Subsequently, the following equation has been offered [8] (8) where B is defined by the following relation B-- (9) where a is the cross-sectional area and R is the ratio of the polar moment of inertia of this crosssectional area to the "shape factor" [9] for the same cross section. The following approximation for rectangular cross section is given by Pickett [7] and based on Roark's Monograph [9], R--e/w-\-w/e '4(e/w)-2.52(e/w)2+0.21(e/w)« (10) A reexamination of the accm-acy of the equation for R for the dynamic shear modulus calculations has been presented [10].…”

Effect of Rate of Strain on the Strength of Remolded Soil

“…As regards the moduli of elasticity of steel, copper, aluminum, lead, nickel and tungsten, work by Ide (7), Sears (8) and King (9) showed that it is independent of time of loading. Also, King (10) studying copper and molybdenum found that the shear modulus of these materials is not influenced by the time of loading.…”